利用电流行波进行超高压输电线路故障类型识别的研究

通过对超高压输电线路各种类型故障的特征分析，提出了一种综合利用暂态电流行波幅值和极性的故障特征来识别故障类型的新原理，指出零模量和线模量之间的幅值关系不宜被用以构造识别判据。文中还设计出基于小波变换的故障类型识别的实用快速算法，该快速算法能免受TA饱和、系统振荡的影响，提高了以往行波故障选相方案在单相或两相接地故障时的可靠性。大量ATP仿真数据的测试表明：这种故障类型识别的新原理及其算法在线路不同位置、不同过渡电阻、不同初始角等故障情况下都能正确快速地选出故障相。现场实录故障数据也验证了该故障类型识别方法是可行的。

STUDY OF FAULT-TYPE IDENTIFICATION USING CURRENT TRAVELING-WAVES IN EXTRA-HIGH-VOLTAGE TRANSMISSION LINES

This paper first analyses the characteristics of various type faults in EHV transmission lines. Then a novel principle of fault-type identification is presented, which synthetically uses the magnitude / polarity characteristics of fault-induced current traveling-waves. And the paper indicates that the magnitude relation between zero- and aerial-mode components is unfit to form identification criterions. The paper also designs the speedy wavelet-based algorithm of the fault-type identification. The algorithm is immune to CT saturation and power swing, and improves the reliability in identifying single / two-phase-to-ground faults with previously proposed phase selection schemes based on traveling waves. A large number of ATP simulation tests show that the new fault-type identification method can correctly select the faulty phase on various conditions involving different fault positions, different fault path resistances and different inception angles. The field-recorded fault data also verify that the novel approach is feasible.